Water chiller



FIG. 1 is a perspective view of a water chiller showing a new design;

FIG. 2 is a front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a right side view thereof;

FIG. 5 is a left side view thereof;

FIG. 6 is a bottom view thereof; and,

FIG. 7 is a top view thereof.

The broken lines in the drawings are included for the purpose of illustration and form no part of the claimed design. 

The ornamental design for a water chiller, as shown. 